In WO 00/26483 a method and a profile for connecting building blocks is described resulting in a wall in a building system. According to this method, two construction blocks are joined along an edge face of each block abutting each other by a profile having a web and two flanges on each side with a perpendicularly extending flap at the distal ends of these two flanges. These flaps are inserted into a groove in the construction blocks whereby the blocks are held together.
This method is advantageous since prefabricated construction blocks may be provided off site and transported to the building site together with other materials and may be assembled on the building site. However, if the rectangular frame is subjected to a twisting force, the gripping flanges may slide out of the slits in the insulation making the entire building system unstable.